Step 1) Go to wikiStep 2) scroll to bottom of pageStep 3) read through the piles of sources right there

Don't avoid bias sources, simply understand that they are bias and only giving you part of the story, and gather bias from both sides (as well as unbiased). Part of understanding history is also understanding how others viewed it. Since every aspect of recorded history is recorded by a person, who may or may not have biases.